As shown in FIG. 1A, images in a garment gallery are currently usually obtained by photographing. FIG. 1A is a schematic diagram illustrating an image in a garment gallery according to the prior art. In FIG. 1A, an upper garment 2 is tried on a plastic model 1. When virtual fitting is conducted, the plastic model 1 should be removed from the image in a garment gallery as shown in FIG. 1A, and the remaining is synthesized with a picture provided by a user. As shown in FIGS. 1B and 1C, FIG. 1B is a schematic diagram illustrating an image of the upper garment with the plastic model removed according to the prior art. As shown in FIG. 1B, the rear collar of the upper garment 2 is blank and a notch 3 is formed. FIG. 1C is a schematic diagram of the virtual fitting according to the prior art. As shown in FIG. 1C, gaps 51 and 52 are present on the rear collar after synthesizing image 4 provided by a user with the image of the upper garment with the plastic model removed, which leads to unreal effect and affecting the user's experience.